Structures of Weak-Mixing Matrices As a Consequence of Broken Mirror Symmetry

A model of symmetry breaking is described for a system that may spontaneously choose between a left-handed and a right-handed weak current. For a hierarchic structure of the fermion mass spectrum, this mirror-symmetric system permits reproducing all qualitative properties of the weak-mixing matrices for both quarks (CKM matrix) and leptons (PMNS matrix) without numerically adjusting model parameters. The hierarchy of the CKM matrix elements is directly related to the hierarchic mass spectrum of quark generations. Qualitative properties of the PMNS matrix arise in the case where the spectrum has an inverse character (@ is the smallest mass) and where the Standard Model neutrino is a Dirac particle. A relative smallness of the neutrino-mixing angle @ is due here to the smallness of @ and the smallness of the charged-lepton mass ratio 
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